U.S. patent number 6,582,688 [Application Number 10/088,077] was granted by the patent office on 2003-06-24 for method for extracting compounds of furan lipids and polyhydroxylated fatty alcohols of avocado, composition based on said compounds, and therapeutic, cosmetical or food use of said compounds.
This patent grant is currently assigned to Pharmascience. Invention is credited to Nicole Broutin, Jacques Legrand, Antoine Piccirilli.
United States Patent |
6,582,688 |
Broutin , et al. |
June 24, 2003 |
**Please see images for:
( Certificate of Correction ) ** |
Method for extracting compounds of furan lipids and
polyhydroxylated fatty alcohols of avocado, composition based on
said compounds, and therapeutic, cosmetical or food use of said
compounds
Abstract
The invention concerns a method for selectively extracting furan
lipids and polyhydroxylated fatty alcohols of avocado,
characterised in that it comprises steps which consist in:
preparing an unsaponifiable matter of avocado; then in subjecting
the unsaponifiable matter of avocado to a step of molecular
distillation using adjusted temperature and pressure means to
obtain either a distillate comprising mainly furan lipids and
polyhydroxylated fatty alcohols of avocado. Said method enables in
particular to extract selectively furan lipids of avocado having a
furan lipid content of more than 80 wt. %, even close to 98%.
Inventors: |
Broutin; Nicole (Alluyes,
FR), Legrand; Jacques (Neuilly sur Eure,
FR), Piccirilli; Antoine (Versailles, FR) |
Assignee: |
Pharmascience (Courbevoie,
FR)
|
Family
ID: |
9550128 |
Appl.
No.: |
10/088,077 |
Filed: |
March 20, 2002 |
PCT
Filed: |
September 20, 2000 |
PCT No.: |
PCT/FR00/02601 |
PCT
Pub. No.: |
WO01/21605 |
PCT
Pub. Date: |
March 29, 2001 |
Foreign Application Priority Data
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|
|
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Sep 22, 1999 [FR] |
|
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99 11846 |
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Current U.S.
Class: |
424/78.03;
424/725; 424/757; 426/51; 424/769 |
Current CPC
Class: |
C07C
29/80 (20130101); A23L 33/115 (20160801); C07D
307/36 (20130101); A61P 1/02 (20180101); A61P
19/02 (20180101); A61K 8/9789 (20170801); A61P
19/10 (20180101); A61P 17/00 (20180101); A23L
33/105 (20160801); A61P 43/00 (20180101); A61K
8/922 (20130101); A61Q 19/08 (20130101); A61P
25/00 (20180101); A61P 17/02 (20180101); A61Q
19/00 (20130101); C07C 29/80 (20130101); C07C
33/02 (20130101) |
Current International
Class: |
A23L
1/30 (20060101); A61Q 19/00 (20060101); C07C
29/00 (20060101); A61K 8/97 (20060101); A61K
8/92 (20060101); C07D 307/00 (20060101); A61K
8/96 (20060101); C07D 307/36 (20060101); C07C
29/80 (20060101); A01N 065/00 (); A61K 035/78 ();
A61K 031/74 (); A23L 002/02 () |
Field of
Search: |
;424/78.03,725,757,769
;426/51 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2213112 |
|
Feb 1999 |
|
CA |
|
0 493 144 |
|
Jul 1992 |
|
EP |
|
0 775 480 |
|
May 1997 |
|
EP |
|
2 678 614 |
|
Jan 1993 |
|
FR |
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2 678 632 |
|
Jan 1993 |
|
FR |
|
Other References
Rancurel, A.; "L'avocat: son huile et son insaponifiable.
Utilisation cosmeteque"; Perfums, Cosmetiques, Aromes; No. 61,
Feb.-Mar. 1985; Societe D'Expansion Technique et Economique S.A.;
Paris, France; pp 91-95. .
Farines, M., et al.; "Influence of Avocado Oil Processing on the
Nature of Some Unsaponifiable Constituents"; Journal of the
American Oil Chemists' Society, vol. 72, No. 4, 1995; American Oil
Chemists' Society; Champaign; U.S.; pp 473-476..
|
Primary Examiner: Lilling; Herbert J.
Attorney, Agent or Firm: Foley & Lardner
Claims
What is claimed is:
1. A process for selectively extracting the furan lipids and
polyhydroxylated fatty alcohols of avocado, characterized in that
it comprises the steps consisting in preparing an unsaponifiable
material from avocado, and then in subjecting the unsaponifiable
material from avocado to a step of molecular distillation using
temperature and pressure means that are adjusted so as to obtain
either a distillate mainly comprising furan lipids of avocado, or a
distillate mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado.
2. The process as claimed in claim 1, characterized in that, for
the molecular distillation step following that of preparation of
the unsaponifiable material, the temperature means are adjusted for
a temperature of between 100 and 160.degree. C. and the pressure
means are adjusted for a pressure of between 10.sup.-3 and
5.times.10.sup.-2 mmHg.
3. The process as claimed in claim 1, characterized in that, for
the molecular distillation step following that of preparation of
the unsaponifiable material, the temperature means are adjusted for
a temperature of between 100 and 140.degree. C. and the pressure
means are adjusted for a pressure of between 10.sup.-3 and
5.times.10.sup.-2 mmHg, so as to obtain a distillate mainly
comprising furan lipids of avocado.
4. The process as claimed in claim 1, characterized in that, for
the molecular distillation step following that of preparation of
the unsaponifiable material, the temperature means are adjusted for
a temperature of between 130 and 160.degree. C. and the pressure
means are adjusted for a pressure of between 10.sup.-3 and
5.times.10.sup.-2 mmHg, so as to obtain a distillate mainly
comprising furan lipids of avocado and polyhydroxylated fatty
alcohols of avocado.
5. The process as claimed in claim 1, characterized in that the
unsaponifiable material from avocado is prepared from the fruit
that has been heat-treated beforehand.
6. The process as claimed in claim 5, characterized in that the
fruit is heat-treated beforehand by controlled drying at a
temperature of at least about 80.degree. C. for a period of at
least about four hours.
7. The process as claimed in claim 1, characterized in that the
unsaponifiable material from avocado is prepared from the oil of
the fruit that is enriched beforehand in unsaponifiable material by
molecular distillation.
8. The process as claimed in claim 7, characterized in that the
molecular distillation of the oil of the fruit is performed at a
temperature of between about 180 and about 230.degree. C. and at a
pressure of between about 10.sup.-3 and about 10.sup.-2 mmHg.
9. The process as claimed in claim 1, characterized in that the
molecular distillation is performed using a device chosen from
molecular distillation devices of centrifugal type and molecular
devices of scraped-film type.
10. A pharmaceutical composition, characterized in that it
comprises at least one active principle chosen from the group
consisting of distillates mainly comprising furan lipids of avocado
and distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado, as obtained by the process as claimed in
claim 1, and at least one pharmaceutically acceptable
excipient.
11. A cosmetic composition comprising at least one cosmetically
active principle chosen from the group consisting of distillates
mainly comprising furan lipids of avocado and distillates mainly
comprising furan lipids and polyhydroxylated fatty alcohols of
avocado, as obtained by the process as claimed in claim 1, and at
least one cosmetically acceptable excipient.
12. A cosmetic method for treating the skin, neighboring mucous
membranes and/or integuments, characterized in that a cosmetic
composition comprising at least one cosmetically active compound
chosen from the group consisting of distillates mainly comprising
furan lipids of avocado and distillates mainly comprising furan
lipids and polyhydroxylated fatty alcohols of avocado, as obtained
by the process as claimed in claim 1, and at least one cosmetically
acceptable vehicle, is applied to the skin, neighboring mucous
membranes and/or integuments.
13. The method as claimed in claim 12, for the cosmetic treatment
of scars on the skin.
14. The method as claimed in claim 12, for the cosmetic treatment
of intrinsic aging of the skin.
15. The method as claimed in claim 12, for the cosmetic treatment
of skin that has been subjected to actinic radiation.
16. The method as claimed in claim 12, wherein the cosmetically
active compound is present in the cosmetic composition in a
proportion of between about 0.1 and about 10% by weight relative to
the total weight of the cosmetic composition.
17. A food additive, comprising at least one composition chosen
from the group consisting of distillates mainly comprising furan
lipids of avocado and distillates mainly comprising furan lipids
and polyhydroxylated fatty alcohols of avocado, as obtained By the
process as claimed in claim 1.
18. A method of treating articular complaints in a patient
comprising administering to the patient compounds extracted using
the method of claim 1, said compounds chosen from the group
consisting of distillates mainly comprising furan lipids of avocado
and distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado.
19. A method according to claim 18, wherein the articular complaint
is arthrosis.
20. A method according to claim 18, wherein the articular complaint
is arthritis.
21. A method of treating periodontal conditions comprising
administering to a patient compounds extracted using the method of
claim 1, said compounds chosen from the group consisting of
distillates mainly comprising furan lipids of avocado and
distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado.
22. A method according to claim 21, wherein the periodontal
conditions is periodontitis.
23. A method of treating osteoporosis comprising administering to a
patient compounds extracted using the method of claim 1, said
compounds chosen from the group consisting of distillates mainly
comprising furan lipids of avocado and distillates mainly
comprising furan lipids and polyhydroxylated fatty alcohols of
avocado.
24. A method modifying the differentiation of nerve cells induced
with NGF comprising administering to a patient compounds extracted
using the method of claim 1, said compounds chosen from the group
consisting of distillates mainly comprising furan lipids of avocado
and distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado.
25. A method of repairing tissue conditions comprising
administering to a patient compounds extracted using the method of
claim 1, said compounds chosen from the group consisting of
distillates mainly comprising furan lipids of avocado and
distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado.
26. A method according to claim 25, wherein the tissue is skin
tissue.
27. A method of modifying food with a food additive comprising:
extracting compounds using the method of claim 1, said compounds
chosen from the group consisting of distillates mainly comprising
furan lipids of avocado and distillates mainly comprising furan
lipids and polyhydroxylated fatty alcohols of avocado; adding said
compounds to food in proportion of about 0.1 to about 20% by weight
relative to the total weight of food.
28. A cosmetic composition according to claim 11, wherein the
cosmetic composition is a dermocosmetic composition.
29. The method of claim 15, wherein the actinic radiation is UV
radiation.
Description
The present invention relates to a novel process for extracting
furan lipid compounds and polyhydroxylated fatty alcohols from
avocado, and also to a pharmaceutical or cosmetic composition based
on these compounds and to the use of these compounds for
manufacturing a medicinal product, in a cosmetic treatment method
and as a food additive.
Avocado comprises, as is known, particular lipids of furan type,
the main component of which is a linoleic furan: ##STR1##
The furan derivatives of avocado oil have been described in
particular in Farines, M. et al., 1995, J. of Am. Oil Chem. Soc.
72, 473.
It is currently well established that the presence of these furan
compounds in the leaves or the fruit depends not only on the
variety (the varieties Hass and Fuerte being the richest in furan
compounds), but also on the method for obtaining the oil or another
plant extract of avocado (ethanolic or hexane extract of avocado
leaves).
Specifically, it is known that these furan lipids are metabolites
of compounds that are initially present in the fruit and the
leaves, which, due to the effect of heat, become dehydrated and
cyclize into furan derivatives.
For example, linoleic furan is derived from the thermal
transformation of the following precursor: ##STR2##
Moreover, certain compounds initially present in avocado fruit and
leaves may be in the form of nonacetylated polyhydroxylated fatty
alcohols, such as the following compound: ##STR3##
The polyhydroxylated fatty alcohol content in the fruit depends
mainly on the climatic conditions, the quality of the soil, the
season and the maturity of the fruit on harvesting.
In general, the furan lipids of avocado are compounds that are
unique in the plant kingdom and are desired above all for their
pharmacological, cosmetic or even nutritional properties.
However, the known techniques for obtaining these specific
compounds from avocado fruit or from the oil of avocado fruit
amount either to preparative chromatography or to industrial
processes that allow these furan lipids to be obtained only as a
mixture with the other unsaponifiable compounds of avocado, in a
maximum content of furan lipids that is at best between 50% and
about 65% by weight only.
In addition, the known industrial processes require a preliminary
step of molecular distillation of the oil of the fruit to obtain
the furan lipids in contents that are nevertheless still
unsatisfactory. This preliminary step requires the use of high
temperatures, such as temperatures above 180.degree. C. for
pressures of the order of 10.sup.-3 mmHg, which, in industrial
terms, involves a large consumption of energy.
More particularly, the production of furan lipids of higher purity
by molecular distillation of the oil of the fruit ("crude pressed
oil") is industrially difficult given the very acidic nature of the
oil (acid number of about 6 to 10 mg KOH/g), necessitating a
preliminary neutralization by at least partially refining the oil.
Furthermore, such a refining operation, even partial, entails a
consequent loss of furan lipids and thus a reduction in the final
yield of these desired compounds.
It has now been found, entirely surprisingly and unexpectedly, that
the drawbacks of the prior art described above can be overcome by
carrying out a specific process for obtaining a selective
extraction of the furan lipids of avocado with a content of more
than 80% by weight of furan lipids, or even close to 98%.
Moreover, according to one particular embodiment of the process
according to the invention, a selective extraction is
advantageously obtained not only of the furan lipids, but also of
the polyhydroxylated fatty alcohols of avocado.
What is more, the process according to the invention comprises a
step of molecular distillation in which the temperature and
pressure settings may be markedly lower than those of the
abovementioned prior art.
One subject of the present invention is thus a process for
selectively extracting the furan lipids and polyhydroxylated fatty
alcohols of avocado, characterized in that it comprises the steps
consisting in preparing an unsaponifiable material from avocado,
and then in subjecting the unsaponifiable material from avocado to
a step of molecular distillation using temperature and pressure
means that are adjusted so as to obtain either a distillate mainly
comprising furan lipids of avocado, or a distillate mainly
comprising furan lipids and polyhydroxylated fatty alcohols of
avocado.
According to the invention, the expression "furan lipids of
avocado" means the compounds corresponding to the formula:
##STR4##
in which R is a saturated C.sub.11 -C.sub.19 and preferably
C.sub.13 -C.sub.17 linear hydrocarbon-based chain or a chain
comprising one or more ethylenic or acetylenic unsaturations.
According to the invention, the expression "polyhydroxylated fatty
alcohol of avocado" means a polyol in the form of a saturated
C.sub.17 -C.sub.21 linear hydrocarbon-based main chain or a chain
comprising one or more ethylenic or acetylenic unsaturations, and
comprising at least two hydroxyl groups, the hydroxyl groups being
mainly located on one portion of the main chain, preferably toward
one of the two ends of the main chain, the other portion of this
main chain thus constituting the "fatty" chain (hydrophobic
portion) of the polyol.
The unsaponifiable material is the fraction of a fatty substance
which, after the prolonged action of an alkaline base, remains
insoluble in water and may be extracted with an organic solvent.
Five major groups of substances are present in the majority of the
unsaponifiable materials from plant oils: saturated or unsaturated
hydrocarbons, aliphatic or terpenic alcohols, sterols, tocopherols,
carotenoid and xanthophilic pigments.
A comparison of the contents of unsaponifiable materials from
various plant oils: soybean, cotton, coconut, olive and avocado,
shows a very large content of unsaponifiable material from avocado
oil obtained by extraction according to various known processes.
Typically, the contents obtained range from 2 to 7% of
unsaponifiable material in avocado oil, compared with 0.5% in
coconut oil, 1% in soybean oil and 1% in olive oil. The
unsaponifiable material from avocado may be prepared by extraction
starting with avocado oil.
The known processes for obtaining avocado oil are mainly the
following: either the fresh pulp is pressed in the presence of a
water-absorbing intermediary fibrous substance such as coffee husk
in a cage press, and the emulsion of oil and water obtained is then
separated out by settling and/or centrifugation; or the fresh pulp
is ground and is placed in contact with a suitable organic solvent
(for example a methanol/chloroform mixture) and the oil is then
recovered by evaporating off the solvent.
The avocado oil thus obtained is then subjected to an extraction of
the unsaponifiable material, in a known manner.
Several processes have been described for extracting the
unsaponifiable material from a plant oil. All preferably adopt
saponification with potassium hydroxide or sodium hydroxide in
alcoholic medium, preferably ethanolic medium, followed by one or
more extractions with a suitable organic solvent, for example
petroleum ether, ethyl ether or any other suitable solvent that is
immiscible with the aqueous-alcoholic solution.
The extraction solution obtained is then preferably centrifuged,
filtered and then washed with water to remove the residual traces
of alkalinity. Next, the extraction solvent is carefully evaporated
off to recover the unsaponifiable material. Needless to say,
additional operations known to those skilled in the art, such as a
deodorization step, may also be included.
Preferably, the unsaponifiable material from avocado is prepared
from the fruit that has been heat-treated beforehand, before
extraction of the oil and saponification, as described in
particular in patent application FR-91/08301.
This heat treatment consists of a controlled drying of the fruit,
which is preferably fresh, for at least four hours, advantageously
at least 10 hours and preferably between about 24 and about 48
hours, at a temperature preferably of at least about 80.degree. C.
and preferably between about 80 and about 120.degree. C.
It is clearly understood that the drying time and temperature are
two mutually linked parameters as regards the expected result of
the heat treatment, which is to promote the cyclization of the
furan lipid precursors.
Finally, before its saponification, the oil may be pre-enriched in
unsaponifiable material by separating out a majority of the
constituents of the unsaponifiable material that are recovered in a
concentrate. Various methods may be used: cold crystallization,
liquid-liquid extraction, molecular distillation. Preliminary
concentration of the unsaponifiable material of the oil makes it
possible to reduce the consumption of oil during the
saponification. Molecular distillation is particularly preferred,
and is preferably performed at a temperature of between about 180
and about 230.degree. C. while maintaining a pressure of between
10.sup.-3 and 10.sup.-2 mmHg and preferably of the order of
10.sup.-3 mmHg. The concentration of unsaponifiable material in the
distillate may be up to 60%.
In general, the average composition of an unsaponifiable material
from avocado obtained mainly by controlled drying of the fruit,
extraction of the oil by cold pressing, preliminary molecular
distillation of the oil before saponification with ethanolic
potassium hydroxide, extraction of the unsaponifiable material in a
countercurrent column with an organic solvent, filtration, washing,
desolvation and deodorization, is as follows (in percentages by
weight relative to the total weight of the unsaponifiable
material):
polyhydroxylated fatty alcohols 5-25% furan lipids 50-70% sterols
2-4% squalene 0.5-5% others 5-20% (1) (1) free fatty acids,
hydrocarbons, tocopherols, fatty ketones and heavy pigments.
According to the invention, the unsaponifiable material from
avocado obtained as described above is then subjected to a step of
molecular distillation.
According to one particularly preferred embodiment of the present
invention, this step of molecular distillation, combination of
which with the preliminary step of preparing the unsaponifiable
material constitutes an essential characteristic of the present
process, is performed with temperature means adjusted for a
temperature of between 100 and 160.degree. C. and pressure means
adjusted for a pressure of between 10.sup.-3 and 5.times.10.sup.-2
mmHg.
In particular, the temperature means are adjusted for a temperature
of between 100 and 140.degree. C. and the pressure means are
adjusted for a pressure of between 10.sup.-3 and 5.times.10.sup.-2
mmHg, so as to obtain a distillate mainly comprising furan lipids
of avocado.
Moreover, according to one advantageous variant of the present
process, the temperature means are adjusted for a temperature of
between 130 and 160.degree. C. and the pressure means are adjusted
for a pressure of between 10.sup.-3 and 5.times.10.sup.-2 mmHg, so
as to obtain a distillate mainly comprising furan lipids of avocado
and polyhydroxylated fatty alcohols of avocado.
This step of molecular distillation of the unsaponifiable material,
and also any other molecular distillations that may be carried out
in the process of the invention, as described above, are preferably
performed using a device chosen from molecular distillation devices
of centrifugal type and molecular devices of scraped film type.
Molecular distillation devices of centrifugal type are known to
those skilled in the art. For example, patent application EP-0 493
144 describes a molecular distillation device of this type. In
general, the product to be distilled is spread in a thin layer onto
the heated surface (hot surface) of a conical rotor rotating at
high speed. The distillation chamber is placed under vacuum. Under
these conditions, there is evaporation rather than boiling, from
the hot surface, of the constituents of the unsaponifiable
material, the advantage being that the oil and the unsaponifiable
material (these products being notoriously fragile) are not
degraded during the evaporation.
Molecular distillation devices of scraped film type, which are also
known to those skilled in the art, comprise a distillation chamber
containing a rotating doctor blade, allowing the product to be
distilled to be spread continuously over the evaporation surface
(hot surface). The product vapors are condensed by means of a cold
finger, placed in the center of the distillation chamber. The
peripheral feed and vacuum systems are very similar to those of a
centrifugal distillation device (feed pumps, vane vacuum pumps, oil
diffusion pumps, etc.). The recovery of the residues and the
distillates in glass flasks takes place by gravitational flow.
A subject of the present invention is also a pharmaceutical
composition, characterized in that it comprises at least one active
principle chosen from the group consisting of distillates mainly
comprising furan lipids of avocado and distillates mainly
comprising furan lipids and polyhydroxylated fatty alcohols of
avocado, as obtained by the process described above, and at least
one pharmaceutically acceptable excipient.
More particularly, a subject of the present invention is the use of
at least one compound chosen from the group consisting of
distillates mainly comprising furan lipids of avocado and
distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado, as obtained by the process described
above, for the manufacture of a medicinal product intended for
treating articular complaints, more particularly for treating
arthrosis and for treating arthritis (that is to say rheumatoid
arthritis, psoriatic arthritis, Lyme's arthritis and/or any other
type of arthritis).
The medicinal product thus prepared may be intended for treating
periodontal complaints, and in particular for treating
periodontitis.
This medicinal product may moreover be intended for treating
osteoporosis.
In addition, this medicinal product may be intended for modifying
the differentiation of nerve cells that is induced with NGF.
According to the invention, the term "modifying" means the action
of increasing or reducing the differentiation of nerve cells that
is induced with NGF.
Finally, this medicinal product may be intended for tissue repair,
and in particular for repairing skin tissue, especially in the
context of a dermatological use.
Another subject of the present invention is a cosmetic composition,
especially a dermocosmetic composition, characterized in that it
comprises at least one cosmetically active principle chosen from
the group consisting of distillates mainly comprising furan lipids
of avocado and distillates mainly comprising furan lipids and
polyhydroxylated fatty alcohols of avocado, as obtained by the
process described above, and at least one cosmetically acceptable
excipient.
Finally, the present invention also relates to a cosmetic method
for treating the skin, neighboring mucous membranes and/or
integuments, characterized in that a cosmetic composition
comprising at least one compound chosen from the group consisting
of distillates mainly comprising furan lipids of avocado and
distillates mainly comprising furan lipids and polyhydroxylated
fatty alcohols of avocado, as obtained by the process described
above, and at least one cosmetically acceptable vehicle such as the
vehicles generally used in the field of cosmetic products, is
applied to the skin, neighboring mucous membranes and/or
integuments.
Preferably, it is a cosmetic method for treating scars on the skin,
the intrinsic ageing of the skin (that is to say ageing of the skin
not resulting predominantly from an action external to the skin)
and a cosmetic method for treating skin that has been subjected to
actinic radiation, especially ultraviolet radiation.
Preferably, the unsaponifiable material from plant oil is present
in the cosmetic composition in a proportion of between about 0.1
and about 10% by weight relative to the total weight of the
cosmetic composition.
Finally, a subject of the present invention is a food additive,
characterized in that it comprises at least one compound chosen
from the group consisting of distillates mainly comprising furan
lipids of avocado and distillates mainly comprising furan lipids
and polyhydroxylated fatty alcohols of avocado, as obtained by the
process described above.
Finally, the present invention relates to the use of at least one
compound chosen from the group consisting of distillates mainly
comprising furan lipids of avocado and distillates mainly
comprising furan lipids and polyhydroxylated fatty alcohols of
avocado, as obtained by the selective extraction process described
above, as an additive in a food for humans and/or animals, in a
proportion of said compound of between about 0.1 and about 20% by
weight relative to the total weight of the food.
The following examples are intended to illustrate the present
invention and should not in any way be interpreted as possibly
limiting its scope.
Unless otherwise specified, the percentages indicated in the
following examples are percentages by weight.
Example 1: Preparation of an Unsaponifiable Material from
Avocado
100 g of avocado cut into slices about 5 mm thick are subjected to
the following operations:
1.1) Heat Treatment of the Fruit
The sliced fruit is placed in an oven set at 80.degree. C. for 24
hours, and is then ground.
1.2) Production of the Oil
The powder obtained in the preceding step is extracted with hexane
by cold-pressing in a "KOMET" screw press. The cake is removed and
the hexanic solution is evaporated off under reduced pressure. The
oil recovered is filtered through a Buchner funnel and then stored
under nitrogen. 20 g of avocado oil are thus obtained.
1.3) Concentration
A scraped-film distillation device as described above, sold by the
company Leybold under the name "KDL 4", is used. It is a glass
device, equipped with a distillation chamber comprising a rotating
doctor blade, allowing the product to be treated to be spread
continuously over the evaporation surface (hot surface). The
product vapors are condensed by means of a cold finger, placed in
the center of the distillation chamber. The peripheral feed and
vacuum systems are very similar to those of a centrifugal
distillation device (feed pumps, vane vacuum pumps, oil diffusion
pumps, etc.). The recovery of the residues and the distillates in
glass flasks takes place by gravitational flow.
The distillation temperature is about 230.degree. C. with a
pressure of the order of 10.sup.-3 mmHg. The rotation speed of the
shaft is 200 rpm and the feed rate is 7 ml/min.
1.4) Saponification
50 g of oil concentrate obtained as in the preceding step are mixed
with 25 ml of 12N potassium hydroxide and 100 ml of ethanol and
refluxed for 4 hours. 175 ml of water are added to the
aqueous-alcoholic phase, followed by addition of 175 ml of
dichloroethane, and the mixture is stirred and the phases are then
allowed to separate by settling. The organic phase is then
recovered. This operation is repeated 5 to 6 times. The organic
phases are combined and washed with water, and the solvent is
evaporated off. 20 g of unsaponifiable material are thus obtained.
Needless to say, for an industrial-scale preparation, the steps of
extraction in a separating funnel can be replaced with a continuous
extraction in a continuous liquid-liquid extraction machine such as
a pulsed column, a decanting mixer or equivalents.
Example 2: Molecular Distillation of an Unsaponifiable Material
Rich in Polyhydroxylated Fatty Alcohols
An unsaponifiable material is prepared as described above. The
analysis of this unsaponifiable material shows that it is rich in
polyhydroxylated fatty alcohols (about 25%). Its composition is as
follows:
polyhydroxylated fatty alcohols 24.3% furan lipids 55.5% sterols
3.1% squalene 1.4% others 15.7% (1) (1) free fatty acids,
hydrocarbons, tocopherols, fatty ketones and heavy pigments.
2.1) Laboratory Distillation
This unsaponifiable material is subjected to a molecular
distillation using the same "KDL4" scraped-film device from the
company Leybold described above.
However, the distillation conditions are as follows:
hot-surface temperature: 108.degree. C. pressure: 10.sup.-3 mmHg
rotation speed of the shaft: 240 rpm feed rate of unsaponifiable
material from avocado: 400 ml/h
Distillation Yield: 48.6%.
Composition of the distillate:
polyhydroxylated fatty alcohols: n.m. furan lipids 99.1% sterols
n.m. squalene n.m. others 0.9% (1) (1) free fatty acids,
hydrocarbons and fatty ketones ("n.m.": not measurable, that is to
say a content of less than 0.05%).
This is thus a distillate that is very rich in furan lipids since
the content of these lipids exceeds 99%.
2.2) Pilot-scale Molecular Distillation
The same unsaponifiable material from avocado is distilled in a
pilot molecular distillation device (15-25 kg/h) of centrifugal
type, operating continuously, under a vacuum of between 0.01 and
0.05 mm of mercury, and at a temperature in the range from 100 to
150.degree. C.
The results obtained at various temperatures and pressures are
collated in tables 1 and 2 below.
TABLE 1 Extraction of the furan lipids by molecular distillation of
an unsaponifiable material from avocado that is rich in
polyhydroxylated fatty alcohols Content of furan lipids in Feed
Degree of the Temperature Pressure rate distillation distillate
Sample (T.degree. C.) (mmHg) (kg/h) (%) (%) 1 129 0.020 13.3 60.0
93.2 2 123 0.025 13.5 53.6 96.2 3 112 0.050 12.9 47.0 97.7
The degree of distillation is defined as follows: it is the mass
ratio, relative to 100%, of the mass of the distillate to the sum
(mass of the distillate+mass of the residue).
The results collated in table 1 show that the molecular
distillation of an unsaponifiable material from avocado makes it
possible, simply and in a substantial yield, to prepare a fraction
that is very rich in furan lipids of avocado (content of greater
than 97%).
In an identical manner, the results of the tests collated in table
2 show that it is also possible to obtain fractions that are
selectively enriched in avocado furans and polyhydroxylated fatty
alcohols.
TABLE 2 Extraction of the furan lipids and polyhydroxylated fatty
alcohols by molecular distillation of an unsaponifiable material
from avocado that is rich in polyhydroxylated fatty alcohols
Content of poly- Content hydroxy- of lated furan fatty Degree
lipids alcohols of in the in the Feed distil- distil- distil- T
Pressure rate lation late late Sample (.degree. C.) (mmHg) (kg/h)
(%) (%) (%) 4 150 0.015 12.8 79.8 73.5 22.0 5 137 0.025 12.6 85.5
66.9 25.5
In conclusion, this set of tests shows that it is possible, by
molecular distillation of an unsaponifiable material from avocado,
that is rich in polyhydroxylated fatty alcohols, to prepare
distillates of very high purity, selectively comprising a high
content of furan lipids (purity greater than 97%) or a high content
of furan lipids with polyhydroxylated fatty alcohols (sum of the
contents of furan lipids and of polyhydroxylated fatty alcohols
greater than 95%).
Example 3: Molecular Distillation of an Unsaponifiable Material
that is Low in Polyhydroxylated Fatty Alcohols
An unsaponifiable material is prepared as described above. The
analysis of this unsaponifiable material shows that it is low in
polyhydroxylated fatty alcohols (about 4%). Its composition is as
follows:
polyhydroxylated fatty alcohols 3.7% furan lipids 68.7% sterols
6.6% squalene 1.4% others 19.6% (1) (1) free fatty acids,
hydrocarbons, tocopherols, fatty ketones and heavy pigments.
3.1) Laboratory Distillation
This unsaponifiable material is subjected to a molecular
distillation using the same "KDL4" scraped-film device from the
company Leybold as that already described above.
The distillation conditions are as follows: hot-surface
temperature: 108.degree. C. pressure: 10.sup.-3 mmHg rotation speed
of the shaft: 240 rpm feed rate of unsaponifiable material from
avocado: 400 ml/h.
Yield of distillate: 50.8%.
Composition of the distillate:
polyhydroxylated fatty alcohols: 0.2% furan lipids 94.8% sterols
0.1% squalene 0.2% others 4.7%.
This is thus a distillate that is very rich in furan lipids since
its content of these lipids exceeds 94%.
3.2) Pilot-scale Molecular Distillation
The same unsaponifiable material from avocado is distilled in a
pilot molecular distillation device (15-25 kg/h) of centrifugal
type, operating continuously, under a vacuum of between 0.01 and
0.05 mm of mercury, and at a temperature in the range between 100
and 140.degree. C. The results obtained at various temperatures and
pressures are collated in table 3 below.
TABLE 3 Extraction of the furan lipids by molecular distillation of
an unsaponifiable material from avocado that is low in
polyhydroxylated fatty alcohols Content of furan compounds Feed
Degree of in the T Pressure rate distillation distillate Sample
(.degree. C.) (mmHg) (kg/h) (%) (%) 1 115 0.015 20.4 47.8 94.3 2
126 0.015 18.6 65.8 94.2 3 137 0.015 18.5 71.3 93.8
The results collated in table 3 show that the molecular
distillation of an unsaponifiable material from avocado makes it
possible, simply and in a substantial yield, to prepare a
distillate that is very rich in furan lipids of avocado (content of
greater than 94%).
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